1. Field of the Invention
This invention relates to a drawer comprising two metal side walls laterally delimiting an interior of the drawer, each side wall having a laterally inwardly bent bottom flange extending in a longitudinal direction and having a plurality of stamped-out and upwardly bent retaining lugs spaced from each other in the longitudinal direction and extending substantially perpendicularly to the longitudinal direction, and a bottom plate having a bottom surface and extending between the side walls. The bottom surface of the bottom plate is supported on the bottom flanges, and the bottom plate has a front face, a rear end and lateral portions extending between the front face and the rear end adjacent the bottom flanges of the side walls.
The side walls of the drawers may have different heights and they preferably have means for guiding the drawer as it is extended. In particular they may be integrally formed with a guide rail for such guidance. If a rear wall is provided, it extends to the flanges of the side walls of the drawer and abuts the bottom plate. A front wall of the drawer is secured in most cases by separate, adjustable retaining means, independently of the means for fixing the bottom plate.
2. Description of the Prior Art
It is known that the bottom plate may be fixed by means of raised lugs stamped from the carrying flanges and press fit into bores of the bottom plate or into longitudinal grooves, which are formed in the bottom plate and are parallel to its edges. In accordance with British patent No. 2,169,491 the retaining lugs have been bent up around bend lines extending parallel to the longitudinal direction of the flange and extend into continuous grooves, which are formed in the bottom plate and extend parallel to its edges, and the height of the bent-up retaining lugs somewhat exceeds the depth of the groove, which has a small width, which substantially conforms to the thickness of the lugs, so that the pressing of the bottom plate onto the carrying flange will cause the retaining lugs partly to penetrate into the bottom of the groove. Such an arrangement will not ensure a satisfactory anchoring of the retaining lugs in the groove and a lifting of the bottom plate and its displacement along the groove will not adequately be prevented. From U.S. Pat. No. 4,875,747 it is known to provide the bottom plate with a somewhat wider groove and to bend up the retaining lugs about bend lines which include an acute angle with the longitudinal direction of the flange so that the lugs extend obliquely to the groove and their longitudinal edges will cut into the side faces of the groove as the bottom plate is forced onto the carrying flange. Also in that arrangement a lifting of the bottom plate from the carrying flanges will not adequately be prevented and the position to which the bottom plate is forced against the carrying flanges is not exactly defined so that the use of assembling machines must be expected to result in a fixation of the bottom plate with large longitudinal tolerances. In a different embodiment, claws, which can subsequently be bent, are used as retaining means and when they have been inserted into the bore or groove are bent to assume a final position, in which the claws have penetrated into the material which constitutes the side faces of the bore or groove. Such claws have previously constituted the optimum known means for preventing a displacement and lifting of the bottom plate but the mounting of such claws is time-consuming and can hardly be automated and even a subsequent manual bending of the claws will involve a higher risk of damage to the bottom plate and/or the claws. From German patent No. 37 02 238 it is known to provide at the rear end of a guide rail a hook for holding the rear end of a drawer box on its support.